Characterization of Cassava Flour (Manihot esculenta Crantz) with Concentrated Cassava Leaf Protein Obtained by isoelectric precipitation

Autor: Lima, Elaine Cristina de Souza
Přispěvatelé: Srur, Armando Ubirajara Oliveira Sabaa, Feij?, Marcia Barreto da Silva, Silva, Andrea Gomes da, Mathias, Vera L?cia
Jazyk: portugalština
Rok vydání: 2011
Předmět:
Zdroj: Biblioteca Digital de Teses e Dissertações da UFRRJ
Universidade Federal Rural do Rio de Janeiro (UFRRJ)
instacron:UFRRJ
Popis: Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2020-08-21T03:00:33Z No. of bitstreams: 1 2011 - Elaine Cristina de Souza Lima.pdf: 1342129 bytes, checksum: f29d57ab97057aaef1a569c8c0c2cb62 (MD5) Made available in DSpace on 2020-08-21T03:00:33Z (GMT). No. of bitstreams: 1 2011 - Elaine Cristina de Souza Lima.pdf: 1342129 bytes, checksum: f29d57ab97057aaef1a569c8c0c2cb62 (MD5) Previous issue date: 2011-02-28 Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil The utilization of biomass has become a worldwide concern, especially in Brazil, a country rich in diversity and quantity of food. However, thousands of Brazilians still go hungry, while much of the biomass is wasted as is the case of subsistence crops, among which highlights the cassava (Manihot esculenta Crantz), which, during the harvest, has his entire shoot neglected by the field. The leaves of manioc contains important nutrients that could be used in the diet as concentrate Protein that portion (CLPC). Given the nutritional importance of CLPC in function of its amino acid profile and the few studies available on the optimal pH for precipitation of proteins in the extracts, the goal this study was to produce a CLPC by isoelectric precipitation. The cassava after washing with water containing ppm chlorine and rinsed with distilled water, were crushed in the presence of 0.1 M NaOH and sodium metabisulfite 0.05% at a ratio of 1:4 (w: v) using a semi-blender industrial. After successive filtrations followed by decantation and centrifugation, the extracts were divided into clarified six aliquots (each extract) and acidified with 0.1 M HCl until the pH's 5.0, 4.5, 4.0, 3.5, 3.0 and 2.5, respectively. The extract with pH 2.5 was what had a higher protein content 76.25% ? 1.25, being used for preparation of cassava flour with 0, 2.5, 5.0 and 10% of CLPC. The addition CLPC to promote significant increase in protein, ash, lipid, fiber and acidity, and decreased amounts of starch. The meal does not showed levels of cyanide were found to be microbiologically secure in accordance with current legislation. Analysis of the amino acid profile CLPC showed that the CLPC is good source of amino acids, as it has for the most amino acids, levels above those required by the FAO (1985), presenting chemical calculation above 100%, however, is deficient in histidine, methionine and cystine. Sensory cassava flour with 2.5% of CLPC presented the best overall flavor, however, no significant difference in the flours with 0 and 5.0% for CLPC. The application of CLPC was effective for providing flour and sensory acceptability increase the protein quality of cassava flour, a product mainly energy and basic food of the Brazilians, in particular the north and northeast, where the incidence of malnutrition is higher. O aproveitamento de biomassa tornou-se uma preocupa??o mundial, em especial no Brasil, pa?s rico em diversidade e quantidade de alimentos. No entanto, milhares de brasileiros ainda passam fome, enquanto grande parte da biomassa ? desperdi?ada como ? o caso das culturas de subsist?ncia, entre as quais se destaca a mandioca (Manihot esculenta Crantz), que, durante a colheita, tem toda a sua parte a?rea desprezada no campo. As folhas dessa maniva cont?m importantes nutrientes que poderiam ser utilizadas na dieta, como Concentrado Prot?ico dessa por??o (CPFM). Diante da import?ncia nutricional do CPFM, em fun??o do seu perfil de amino?cidos e aos poucos estudos dispon?veis relativos ao pH ideal para a precipita??o de prote?nas em extratos aquosos, o objetivo deste estudo foi produzir um CPFM atrav?s de precipita??o isoel?trica. As folhas de mandioca (Manihot esculentum Crantz) cv. Saracura foram de lavadas com ?gua corrente contendo 100 ppm de cloro livre e enxaguadas com ?gua destilada, foram trituradas em presen?a de solu??o de NaOH 0,1M e metabissulfito de s?dio 0,05%, na propor??o de 1:4 (p:v) com aux?lio de liquidificador semi-industrial. Depois de sucessivas filtra??es e decanta??es seguidas de centrifuga??o, os extratos aquosos clarificados obtidos foram divididos em seis al?quotas (cada extrato) e acidificadas com HCl 0,1 M at? os pH?s 5,0, 4,5, 4,0, 3,5, 3,0 e 2,5, respectivamente. O extrato com pH 2,5 foi o que apresentou maior o teor de prote?nas 76,25% ?1,25, sendo utilizado para elabora??o de farinhas de mandioca com 0; 2,5; 5,0 e 10 % de CPFM. A adi??o de CPFM promoveu aumento significativo nos teores de prote?na, cinzas, lip?deos, fibras e acidez, e diminui??o dos teores de amido. As farinhas n?o apresentaram teores de cianeto e foram consideradas microbiologicamente seguras de acordo com a legisla??o vigente. An?lises do perfil de amino?cidos do CPFM mostraram que o CPFM ? boa fonte de amino?cidos, pois possui, para a maioria dos amino?cidos, n?veis superiores aos requeridos pela FAO (1985), apresentando c?mputo qu?mico superior a 100%, no entanto, ? deficiente em histidina, metionina e cistina. Sensorialmente a farinha de mandioca com 2,5% de CPFM foi a que apresentou melhor sabor global, no entanto, n?o houve diferen?a significativa com as farinhas com 0 e 5,0% de CPFM. A aplica??o do CPFM foi efetiva por proporcionar farinhas com aceitabilidade sensorial e aumentar a qualidade prot?ica da farinha de mandioca, um produto essencialmente energ?tico e base da alimenta??o dos brasileiros, em especial do norte e nordeste, onde a incid?ncia de desnutri??o prot?ica ? maior.
Databáze: OpenAIRE
Externí odkaz: